Best Areas

Demon's Souls

• Stonefang Tunnel
• Boletarian Palace
• Tower of Latria

Dark Souls

• Undead Burg
• Anor Londo
• Painted World of Ariamis
• Oolacile Sanctuary
• Blight Town
• Sen's Fortress

DARK SOULS II: Scholar of the First Sin

• No-Man's Wharf
• Huntsmans Copse
• The Gutter
• Shulva - Sanctum city
• Brume Tower
• Frozen Eleum Loyce

Bloodborne

• Cathedral Ward
• Hemwick Charnel Lane
• Central Yharnam
• Nightmare of Mensis
• Forsaken Cainhurst Castle
• Fishing Hamlet

DARK SOULS III

• Cathedral of the Deep
• Profaned Capital / Irithyll Dungeon
• Grand Archives
• Anor Londo
• Lothric Castle

Best Bosses

Demon's Souls

• Penetrator
• Old King Allant
• Flamelurker
• Old Hero

Dark Souls

• Chaos Witch Quelaag
• Ornstein and Smough
• Artorias the Abysswalker
• Manus, Father of the Abyss
• Sanctuary Guardian
• Bell Gargoyles
• Black Dragon Kalameet

DARK SOULS II: Scholar of the First Sin

• The Pursuer
• Smelter Demon
• Sinh, the Slumbering Dragon
• Fume Knight
• Burnt Ivory King

Bloodborne

• Shadow of Yharnam
• Martyr Logarius
• Father Gascoigne
• Ebrietas, Daughter of The Cosmos
• Gehrman, The First Hunter
• Mergo's Wet Nurse
• Yharnam, Pthumerian Queen
• Lady Maria of the Astral Clocktower
• Ludwig, The Holy Blade
• Orphan of Kos

DARK SOULS III

• Old Demon King
• Dragonslayer Armour
• Champion Gundyr
• Lothric, Younger Prince and Lorian, Elder Prince
• Nameless King
• Soul of Cinder

Sekiro: Shadows Die Twice

I'll have to add in the Mini-bosses

• Genichiro Ashina
• Lady Butterfly
• Headless and Guardian Ape
• Corrupted Monk